On 04/09/2011 03:56 AM, wgu wrote:
I have used R for years but run into a seemingly simple problem involving 'ifelse'. condensed code like thisa=c(2,NA,NA,NA,2,2,NA,2,NA,2) b=c(NA,1,1,NA,2,2,2,2,2,2) #I want to combined a and b into c so that c would be a valid number either a or b is not missing c=ifelse(a==1|b==1,1,ifelse(a==2|b==2,2,NA)) cbind(a,b,c) a b c [1,] 2 NA NA [2,] NA 1 1 [3,] NA 1 1 [4,] NA NA NA [5,] 2 2 2 [6,] 2 2 2 [7,] NA 2 NA [8,] 2 2 2 [9,] NA 2 NA [10,] 2 2 2 look at rows 1, 7 and 9, c supposes to be 2 but got NA instead. seemingly, the second 'ifelse' doesn't perform as it supposes. my R version is 2.12.2 any suggestion
Hi wgu, c<-ifelse(is.na(a),b,a) Jim ______________________________________________ R-help@r-project.org mailing list https://stat.ethz.ch/mailman/listinfo/r-help PLEASE do read the posting guide http://www.R-project.org/posting-guide.html and provide commented, minimal, self-contained, reproducible code.
